As it is type 2 diabetes prevention week, we wanted to address a very current and important topic – remission of type 2 diabetes.
For a long time, type 2 diabetes was thought of as a chronic, progressive disease that could not be reversed. However, thanks to groundbreaking research in recent years, it is now being widely appreciated that the condition can be prevented, managed and even placed into remission via a number of methods. Alongside pharmacological therapy and bariatric surgery, which provided the first evidence of type 2 diabetes remissio, some newer dietary approaches are showing some promising results.
In this article, we will explore three strategies that can be employed to put type 2 diabetes into remission. These strategies are: bariatric surgery, a very low calorie diet and a low carbohydrate lifestyle. We’ll discuss what each of these methods entails, how they each result in remission and in which circumstances they may or may not be applicable.
1 – Low carb lifestyle
What is it?
A low carbohydrate, or low carb, lifestyle involves the reduction or restriction of carbohydrate in the diet. Carbohydrate is one of the three macronutrients, along with fat and protein. Definitions of low carb vary, but the consensus seems to be that eating 130 grams, or less, per day is a low carb diet. Many people choose to go lower than this, upon seeing results, and some people restrict carbs to a level below 50 grams per day, which is usually known as a very low carb, ketogenic diet [1].
On a low carb lifestyle, starchy foods such as bread, rice, pasta and potatoes are largely restricted. Foods such as beans and lentils, and sugary fruits like bananas and grapes may also be consumed in smaller amounts, depending on the individual carb goal. Counting calories is not a focus with this way of eating. This can be unusual for some people initially, especially those who have spent many years religiously counting calories. The energy from carbs are replaced with higher levels of healthy fats, such as those found in olives, avocado, nuts and oily fish. Protein intake usually remains around the same as a standard diet.
As many of the high carb foods available today are highly refined and processed, such as crisps and cakes, a well-formulated low carb lifestyle tends to also be low in processed foods, thereby often making it a ‘real food’ lifestyle.
This way of eating has gained much traction over the last decade or so, with an explosion in scientific research in the low carb field. The effectiveness of a low carb approach for type 2 diabetes is now recognised by multiple health authorities internationally, including the American Diabetes Association and the British Dietetic Association [2] [3]. In addition, our own Low Carb Program is now approved in the NHS app library.
How does it result in remission?
Type 2 diabetes can be thought of as a disease of carbohydrate intolerance. The body can no longer create enough or use the hormone insulin effectively, as it has become insulin-resistant. What this means is, the body struggles to move carbohydrate out of the blood and into cells, causing blood glucose levels to rise, which, if this occurs chronically, is what causes the damaging complications of diabetes.
When we eat carbs, these are digested into glucose and absorbed through our gut, into the blood. This raises blood glucose levels. Therefore, if less carbs are eaten, less glucose enters the blood after a meal, therefore requiring less insulin to keep blood glucose stable.
When switching to a lower carb lifestyle, the positive results can be seen almost instantaneously. The post prandial (or after meal) blood glucose level can drop dramatically on a lower carb diet, independent of weight loss. For this reason, some people with type 2 diabetes like to check their blood glucose levels after a meal, finding their own personal carb tolerance. It has been shown that a low carb lifestyle can in fact reverse insulin resistance, returning blood glucose levels to normal, without the need for medication, thus placing type 2 diabetes into remission. Our own Low Carb Program results have shown that one in four people achieve remission at one year [4]. These results were accompanied by an average weight loss of 7.4 kg (1st 2 lbs), and 40% of people were able to eliminate one or more medications from their regime.
A low carb lifestyle lowers insulin levels, increasing the body’s ability to burn fat. This is why the low carb lifestyle is so effective for weight loss.
There is a period of adaptation when switching to a low carb way of eating, and this is usually around two weeks. During this time, you may experience side effects such as tiredness, hunger, light-headedness, headaches and muscle cramps. These soon pass as the body adapts, however, and can often be avoided by staying hydrated and getting enough electrolytes.
The low carb lifestyle is particularly useful as it is not only able to bring about remissio, but it also allows many people to make other positive lifestyle changes too, without extra effort. For example, many people find that they naturally become more active after adapting to low carb.
Is it right for me?
The best diet is one that you can stick to. You may find a low carb diet works for you.
Pros:
- Positive results of a low carb lifestyle can be seen quickly (reduction in blood glucose levels from your first low carb meal)
- Many people report feeling satiated and full, perhaps making it more sustainable in the long term
- A lifestyle change, which can be undertaken by almost anyone
- Does not require you to qualify as obese to practice it, unlike a very low calorie diet or bariatric surgery
- Side effects are minor compared to other remission methods.
Cons:
- Requires the initial motivation and willpower to change eating habits
- You may have some side effects for the first week or so
- You will need to discuss a low carb lifestyle with your healthcare professional if you are taking diabetes or blood pressure medication, to ensure there is no risk of hypos.
2 – Very low calorie diet
What is it?
A very low calorie diet (VLCD), or very low energy diet (VLED) is a diet which consists of consuming between 600-800 calories (kcal) per day. For reference, the standard recommended energy intakes are 2,000 kcal per day for women and 2,500 kcal per day for men. This is therefore a method of extreme calorie restriction.
Such a diet to some may be seen as an extreme measure. It is also usually only considered for those with a body mass index (BMI) over 30, which qualifies as obese, and should be done under medical supervision. A VLCD is usually done for 12 – 20 weeks [5].
A VLCD can be formulated in a number of ways. One option is total diet replacement, where all meals are provided and only a small amount of preparation is required. This is usually a predominantly liquid diet, consisting of commercial, specially formulated, nutritionally complete meal replacement shakes and soups, though there are also meal replacement bars too. These are consumed for an agreed period of time for maximal weight loss, before normal food is then gradually reintroduced, usually one meal at a time.
Technically, one can also create a VLCD using real foods while eating to a goal of around 800 kcal per day. This would require more planning and preparation, as the meals would not be pre-weighed or made. There would also need to be a consideration of how nutritionally complete the diet is, that is, if enough essential vitamins, minerals and other key nutrients are present to maintain health. Again, this should not be done without medical supervision.
VLCDs are not a first-line option and should only be considered after trying other dietary and lifestyle changes. If your GP agrees that a VLCD is a good fit for you, and you wish to go ahead with it, you will then need to find a VLCD provider or specialist dietitian. Your GP may be able to signpost you to a VLCD provider.
How does it result in remission?
A VLCD does what it says on the tin. In short, extreme calorie restriction is the mechanism by which it exerts its beneficial effects on obesity and type 2 diabetes.
Much of the groundbreaking work around VLCDs has come from the DiRECT study, led by professor Roy Taylor at Newcastle University. Early studies tested the hypothesis that a reduction in fat in the liver and pancreas could “wake up” the beta cells in the pancreas. More recently, the DiRECT study done by teams at Newcastle and Glasgow found that just under 50% of the cohort were in remission at one year, this fell to 36% at two years [6] [7]. It is worth noting that the participants had all been diagnosed with type 2 diabetes for a maximum of six years before beginning the intervention. This tells us that the shorter the duration of diabetes, the more likely remission is possible. This is an important finding, showing that early intervention is necessary.
This study has given us a robust understanding of the mechanism of successful remission with VLCD. Magnetic resonance imaging showed that loss of fat from the liver and pancreas predicts remissio, as fat accumulation in and around these organs is largely responsible for the insulin resistance seen in type 2 diabetes [8].
Is it right for me?
Pros:
- Rapid weight loss and diabetes remission in around half of people at 1 year.
- Nutritionally complete meal replacements can be used, so little preparation is required if using this method.
- This diet, if done with the aim of longer-term dietary changes and positive habits, may be a good “kick-start” into a new lifestyle.
- Many people report the “break” from preparing food enjoyable and refreshing
- Surprisingly, some people report better energy and satiety while following a VLCD.
Cons:
- VLCDs can be difficult for some people to stick to, especially during special social occasions.
- Many people find that they regain the weight they lost and undo their progress upon returning to normal food [5]. For this reason, ongoing support from a healthcare professional or specialist is crucial in the long-term success of a VLCD.
- Side effects include low energy, diarrhoea, constipatio, cramps, headaches, nausea and vomiting, dizziness, dry mouth, dry skin and thinning hair
- Meal replacements consist of processed foods such as packet shakes, soups and bars, which are often relatively high in sugar.
- You may not be referred to this option unless you qualify as obese (BMI over 30)
3 – Bariatric surgery
What is it?
Bariatric surgery, also known as obesity surgery, metabolic surgery or weight loss surgery, is a treatment used for people with obesity or obesity-related type 2 diabetes.
There are a number of procedures that fall under the umbrella of bariatric surgery, such as gastric banding, sleeve gastrectomy and Roux-en-Y gastric bypass (RYGB). These all vary slightly in terms of effectiveness and complications, but they all have the same aim: to result in the patient wanting or needing to eat less.
Gastric banding is when an inflatable silicone device is fitted around the top of the stomach to restrict food entry. The tightness of the band can be adjusted by a surgeon and it can later be removed if appropriate.
Sleeve gastrectomy surgery involves cutting out around 70% of the stomach, along its curvature, leaving the stomach looking like a tube or ‘sleeve’. This surgery is not reversible.
The RYGB is the heavy hitter of the three surgeries. Here, the stomach is divided up, leaving a small pouch at the top, and the small intestine is reassembled used to connect this pouch to a lower section. This not only reduces the size of the stomach, but also bypasses much of the small intestine too. The RYGB is the most effective of the three surgeries in terms of weight loss and diabetes remissio, with remission rates between 75% and 90% [9].
Other surgeries performed include the mini-bypass, gastric balloons and duodenal switch (a two-stage operation).
Bariatric surgery results in rapid weight loss, as the patient is no longer able to, or interested in eating to the same capacity as before. Following a healthy lifestyle post-surgery is also required to maintain the benefits. Contrary to popular believe, bariatric surgery is not an “easy way out”. Patients must demonstrate significant lifestyle changes in order to qualify for bariatric surgery.
In the UK, most bariatric surgery is provided by the NHS. The NHS have specific criteria that need to be fulfilled. In order to get a referral, you must:
- Have a BMI of 40 kg/m2 or more, or a BMI between 35 and 40 kg/m2 with an obesity-related condition such as type 2 diabetes or high blood pressure
- Have tried all other weight loss methods, such as dieting and exercise, but have struggled to lose weight of keep it off
- Agree to long-term follow-up and adherence after surgery – such as maintaining healthy lifestyle changes and attending regular check-ups
- Be fit and healthy enough to have surgery under general anaesthetic
- Have received, or plan to receive, treatment from a specialist obesity team [10].
How does it result in remission?
Bariatric surgery is effective for preventing the onset of type 2 diabetes and placing it in remission. The full details of exactly how bariatric surgery results in remission have yet to be elucidated. However, it is known that these procedures result in various structural and functional changes in the gastrointestinal system, which affect how food is digested, absorbed and processed.
Firstly, perhaps the most obvious mechanism is the physical alterations made to the stomach. All forms of bariatric surgery limit how much food is able to enter the stomach at one time, and so this results in caloric restriction. A large decrease in appetite in this way is, at least in part, responsible for the massive weight loss seen with bariatric surgery. It is known that successful remission is closely linked to weight loss in obesity-related type 2 diabetes [6].
Secondly, bariatric surgery results in profound changes to gut hormones, of which there are many. We will take a look at just a few here. Levels of glucagon-like peptide 1 (GLP-1), which is an incretin hormone, increase. The links between this and the weight loss seen with bariatric surgery are poorly understood, however GLP-1 does improve the body’s insulin response, allowing tighter control of blood glucose levels [11]. Levels of a similar hormone known as oxyntomodulin (OXM) are also increased, and this helps to promote satiety (fullness) while increasing energy expenditure [11]. Peptide YY (PYY) is a gut hormone that helps to regulate appetite and has been found to be particularly important for weight loss in rodents following bariatric surgery [11].
Finally, other mechanisms which are not as well understood are changes to the gut microbiome and bile salts, which may play a role in remission [12].
Is it right for me?
Pros:
- Results in very fast weight loss
- Has the highest rates of remission for those with obesity-related type 2 diabetes
- Works through both anatomy and physiology to reduce hunger and improve glucose and insulin responses to food
- Can be a powerful catalyst for change in motivated individuals
- Insulin and other diabetes drugs can often be stopped immediately following surgery.
Cons:
- This is life-changing surgery that is not to be taken lightly and, in the case of sleeve gastrectomy, is completely irreversible
- Post-operative texture progression must be strictly followed after surgery
- Absorption of nutrients from food is impaired and so lifelong supplementation may be required
- There is a risk of complications from the surgery and from the anaesthesia, however this is usually no more dangerous than having a gallbladder removed. Your bariatric team or GP can discuss this with you
- Limited availability, based on the eligibility criteria mentioned above
- Can sometimes result in excess skin due to rapid weight loss, removal of which is not usually offered on the NHS
Which strategy is right for me?
Hopefully, the information in this article will allow you to weigh up some of the pros and cons of each remission strategy and begin thinking about which of these may or may not apply to you personally.
If you are considering trying any of these options, you should consult your healthcare team for more information and for clinical advice.
References
